A valve of the type referred to above is known from European application EP-A-223 051. This known valve is located in the venting line of a fuel tank of a motor vehicle. The valve body is pressed against the valve seat by means of opening movement of a locking flap of the fuel tank lock, so that the valve is closed and the connection between the gas space of the fuel tank and the external surroundings is accordingly interrupted. Accordingly, an air pocket always remains in the fuel tank for reasons of safety. The known valve is only suitable for a tank venting line, i.e., a gas line along which very small amounts of gas must flow per unit of time. The known valve is accordingly not suitable for a system in which the gasoline vapor displaced from the tank during fueling of a motor vehicle is directed to an activated charcoal adsorption filter.
Such a device for intercepting fuel vapors during the filling a fuel tank is known German Patent Application DE-A-37 04 641. In the known device, the valve is a magnetic valve which is actuated via a protective pipe contact controlled by means of the locking flap. Such a solution is costly and expensive and, moreover, has the disadvantage that the vehicle can no longer be filled with fuel during failure of the magnetic valve. The possibility of a mechanical actuation of the shut-off valve is also described in this application.